package yh;

/**
 * 标识符
 */
public class IdentifierDemo {
    public static void main(String[] args) {
        //数字不能开头
        //int 1a=2;
        //数字字母_$组成
        int a1_$=3;
        //驼峰式
        int userAge=12;
        final char User_SEX='女';
        System.out.println(a1_$);
        System.out.println(userAge);
        System.out.println(User_SEX);
    }
}
